LXR linux/include/crypto/poly1305.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Common values for the Poly1305 algorithm
   4 */
   5
   6#ifndef _CRYPTO_POLY1305_H
   7#define _CRYPTO_POLY1305_H
   8
   9#include <linux/types.h>
  10#include <linux/crypto.h>
  11
  12#define POLY1305_BLOCK_SIZE     16
  13#define POLY1305_KEY_SIZE       32
  14#define POLY1305_DIGEST_SIZE    16
  15
  16struct poly1305_key {
  17        u32 r[5];       /* key, base 2^26 */
  18};
  19
  20struct poly1305_state {
  21        u32 h[5];       /* accumulator, base 2^26 */
  22};
  23
  24struct poly1305_desc_ctx {
  25        /* key */
  26        struct poly1305_key r;
  27        /* finalize key */
  28        u32 s[4];
  29        /* accumulator */
  30        struct poly1305_state h;
  31        /* partial buffer */
  32        u8 buf[POLY1305_BLOCK_SIZE];
  33        /* bytes used in partial buffer */
  34        unsigned int buflen;
  35        /* r key has been set */
  36        bool rset;
  37        /* s key has been set */
  38        bool sset;
  39};
  40
  41/*
  42 * Poly1305 core functions.  These implement the ε-almost-∆-universal hash
  43 * function underlying the Poly1305 MAC, i.e. they don't add an encrypted nonce
  44 * ("s key") at the end.  They also only support block-aligned inputs.
  45 */
  46void poly1305_core_setkey(struct poly1305_key *key, const u8 *raw_key);
  47static inline void poly1305_core_init(struct poly1305_state *state)
  48{
  49        memset(state->h, 0, sizeof(state->h));
  50}
  51void poly1305_core_blocks(struct poly1305_state *state,
  52                          const struct poly1305_key *key,
  53                          const void *src, unsigned int nblocks);
  54void poly1305_core_emit(const struct poly1305_state *state, void *dst);
  55
  56/* Crypto API helper functions for the Poly1305 MAC */
  57int crypto_poly1305_init(struct shash_desc *desc);
  58unsigned int crypto_poly1305_setdesckey(struct poly1305_desc_ctx *dctx,
  59                                        const u8 *src, unsigned int srclen);
  60int crypto_poly1305_update(struct shash_desc *desc,
  61                           const u8 *src, unsigned int srclen);
  62int crypto_poly1305_final(struct shash_desc *desc, u8 *dst);
  63
  64#endif
  65